djc4909,
You are correct it is unlikely. It didn’t register fully in my brain when I read your first post.
Normal behavior of this test is:
The only test that will pass with just the blue PCDR loopback adapter attached is the Network External Loopback Test (the last test in the group). The other 4 test will fail.
Network Cable Test, Network Link Test, TCP/IP Internal Loopback and TCP/IP Network Communication Test all require a valid TCP/IP Ethernet connection.
The External Loopback Test is a MAC Address loopback and normally does not require a valid TCP/IP Ethernet connection. I have seen some systems that the NIC seems to disable itself when there is not a valid Ethernet network present, these would fail the External Loopback Test unless it had a link light and a valid TCP/IP connection. This may be what you are seeing.
May I ask what type of system and network card you have? I can see if I can duplicate the behavior here in the Lab.
-Fred